If you want, you can try this, if you're using my plugins (if you want to convert HDR PQ to SDR) :
Code:
video=FFVideoSource("HDRVideo.mkv")
video=video.ConvertBits(16).ConvertToYUV444()
video=Spline36ResizeMT(video,1920,800,SetAffinity=false).Sharpen(0.2)
video=ConvertYUVtoLinearRGB(video,Color=0,OutputMode=2).DGHable(...)
video=ConvertLinearRGBtoYUV()
video
If you don't need separate tuning,
DGHable will very probably be faster than my
ConvertRGB_Hable_HDRtoSDR.